Examining government, state, municipal, federal, and military facilities: Electrical, power, and lighting
Government and military projects are among the toughest challenges an engineer can face. Demanding facility owners, tight budget limitations, safety concerns, and other factors all come into play. Here, engineers with experience in the field offer advice on how to succeed in regards to electrical, power, and lighting.
- Roger Chang, PE, LEED Fellow, Principal, DLR Group, Washington, D.C.
- Shem Heiple, PE, LEED AP, Associate Principal, Senior Mechanical Engineer, Interface Engineering, Portland, Ore.
- Dalrio Lewis, PE, Project Engineer, RTM Associates, Orlando, Fla.
- Spencer Morgenthau, CPSM, LEED AP, Director of Business Development, Southland Energy, a division of Southland Industries, Sterling, Va.
CSE: What are some key differences in electrical, lighting, and power systems you might incorporate in government, state, municipal, federal, and military facilities, as compared with other projects?
Heiple: Two common traits these projects share, as compared with other projects, are the need for longevity for all building systems as well as a code- and often civic-directed need for resiliency during emergencies. Choices for LED lighting and digital lighting controls are and should be driven by the projected energy savings over a building’s lifespan of 30 years. We still see many existing fluorescent lighting systems in retrofit projects that date from the 1980s. Disasters like Hurricane Sandy and the 2016 Fukushima earthquake remind us that when wide swaths of the landscape lose all utilities (drinkable water, electricity, telecommunications, natural gas for heating) suddenly civic buildings—including neighborhood schools—become a natural rallying point for helping provide the local community with everything from sleeping cots to food and clothing to a makeshift medical clinic. Backup generators, building Wi-Fi, and working power outlets where you need them become very important.
CSE: How does your team work with the architect, owner, and other project team members so the electrical/power systems are flexible and sustainable?
Heiple: We need to do a lot of listening to the other parties at the table, especially when it comes to understanding the multiple purposes of a building (i.e., K-12 schools being used for summer camps and evening classes aimed at adults). For example, when we heard that one of the building owners in an Oregon school district was tired of tripping breakers for gym power outlets during summer community fairs (multiple 1,000-W food warmers on one 20-amp circuit), but the school didn’t want a big cluster of outlets that would clutter the gym walls or attract vandals, we suggested a 50-amp dryer outlet behind a lockable plate, placed on a generator-backed circuit. Now they can plug a portable power distribution box into the outlet when they temporarily need five or 10 20-amp circuits in one spot for a weekend event—or when it becomes time to open emergency food service following a natural disaster.
CSE: Describe a facility metering or submetering project. What did it include, and what best practices did you include for these facilities?
Heiple: The downside of having a 30-year-old building is that, through regular staff turnover, building settings for lighting controls and BAS may be overridden or modified over the years without understanding why controls were programmed with their initial settings in the first place. Next thing you know, utility bills are going up without knowing the underlying cause. Building commissioning can certainly help resolve these problems, but time and money can be saved if building loads are monitored on a per-electric-panel basis or at least by basic load type (lighting, plug-in loads, building HVAC, for instance), so problems can be easily diagnosed. Submeters for electricity and water can help keep building systems working optimally, which means less consumption and hopefully having polar bears exist for a little while longer.
CSE: Are you seeing more smart grid or microgrid aspects on such projects? If so, how have you served these needs? Are there any issues unique to these projects?
Heiple: We are not yet seeing owners willing to commit to energy-storage systems, and there may be some wisdom in this. Battery-storage densities have improved but are not notably better than what’s already been achieved with lithium-ion technology for light physical density and moderate energy density. Better battery technology is still in development. That said, they want to see electrical systems designed to incorporate this technology in the future. Utilities are increasingly pushing for lighting controls and BAS controls that can throttle down consumption, allow lighting to dim 10% to 25%, and allow temperature ranges to stretch a little wider so power demand can be reduced at peak times or deferred to later hours of the day for thermal-energy storage.
CSE: What types of unusual standby, emergency, or backup power systems have you specified for government, state, municipal, federal, and military facilities? What were the project goals?
Heiple: We have a federal project where we are investigating the use of a flywheel uninterrupted power supply (UPS) as a stop-gap for brief power outages (<5 seconds), which aren’t long enough to trigger generators to run but can cause wear and tear on electronic power supplies for computers, LED lighting, and HVAC variable frequency drives (VFDs) and early failure of equipment. The beauty of these flywheel UPS systems is that, at most, they provide 20 to 30 seconds of backup power, which is perfect for pairing with a reliable multigenerator backup power system. This enables the owner to avoid the cost and environment expense of heavy metal (lead, cadmium)-based battery-backed UPS systems.